This tablehooter from 2003 (keyboard PCB date label) appears to be the
direct successor of the absurd Golden
Camel 7A - one of the certainly worst keyboards of the world.
Although it has a very similar case, this one doesn't contain the archaic
monophonic tooting Yogmei transistor tone generator with sheet metal
contacts anymore. Instead it has now 8 monophonic digital preset sounds,
2 note polyphonic demos and the drumpads play now 7 real sampled percussion
noises and some rhythm patterns.

In spite of these modernization, the Golden Camel 11AB is still
one of the worst tablehooters ever, since (in unmodified state) especially
the rhythm of this yelling beast distorts horribly, and there are only
2 volume settings (ear tormenting loud - and louder!). In spite of this
the rough digital sounds can be nice for tekkno. (Unfortunately the rhythm
CPU of my specimen is faulty and makes mess after half a minute.)

The 7 leftmost keys are fake and do the same like the 4 drumpads. Although
the case bottom this instrument has a proud "Miles® - quality
certificate" sticker, the hardware of this bad hoax is no quality product
at all, but looks like soldered together as piecework in a Chinese concentration
camp; like the Golden Camel 7A it is an incredible mess of loose
cables, and even the main CPU (a tiny COB module) rumbles loosely around
and hangs only on thin wires - ready to make a short circuit with everything
that comes in its way. Also the control panel still uses metal contacts
of questionable reliability, and the button panel is still fake since all
alphabet letter buttons {"A".."L"} on each half are internally connected
and do the same. And worst - the yellow "DC 9V" AC adapter jack is still
wired parallel(!) to the battery compartment, thus any attempts to use
it with batteries inserted, may cause the batteries to EXPLODE (and also
the microphone would certainly not survive to be accidentally plugged in
here instead of the identical "karaoke" jack below it).

This pile of mess is the original hardware in unmodified state (no joke!).

The main CPU hangs on loose, long cables - ready to make a short circuit
with everything that comes in its way...

Also the rhythm CPU is not held much better by only 2 thin bare wires.

The packaging box tells the model name "GC-11AB" and a different
version of the instrument with a "tone" switch ("piano/ organ") instead
of the "MIC" switch, no percussion symbols on the leftmost keys and both
button panel halves labelled "eight music selected" (like the Golden
Camel 7A) instead of "voice" and "demo songs". The box also includes
the following wrong and very Engrish misspelled technical data list:

The brand name "Miles" (which appears only on the case but nowhere
on this box) seems to be a synonym for "Yongmei", that was alternatively
used on many tablehooters in the same analogue transistor hardware class
like the Golden Camel 7A. Unfortunately the stylish camel logo of
the 7A is missing on the 11AB; possibly the lung cancer manufacturer
Camel
sued Yongmei the ass off because it resembled too much their cigarette
box logo.

main features:

wacky plastic case that imitates a modern stereo keyboard (2nd grill is
fake without holes)

main voice sound generator based on static digital waveforms with volume
envelope. The waveforms have very low sample resolution and thus have audible
beeping aliasing noise in low notes. The timbres otherwise remind to filtered
multipulse squarewave and turn a bit brighter during volume decay. The
envelopes sound rather linear and thus fade silent too soon, which sounds
a bit unrealistic.

notes:

Unlike the Golden Camel 7A, the
key contacts of the 11AB are no wacky sheet metal switches anymore,
but a modern PCB (labelled "MLS11AB 2003/07/16 Zk") with silicone
contacts, and also the keys itself are slightly less flimsy now and have
plastic hooks underneath against bending them upward. But the rest is still
a similar horrible cable- and metal switch mess like inside the 7A.
Initially one of the drumpads didn't work by a wrongly mounted contact
spring. Bizarre is also that all PCBs are made from different materials.

All Buttons and switches scrape with metal on bare copper
traces.

Due to the battery explosion risk by the parallel wired AC- adapter
jack, this Chinese thing contradicts the "CE" rules and thus would be theoretically
illegal to import into the EU (and certainly USA too). To fix this, solder
each a diode into the line from the battery compartment "+" output
to the electronics and from the AC- jack "+" to the electronics.
Initially the rhythm sounded extremely thin, harsh and distorted. To fix
this, disconnect at the amplifier the audio cable from the rhythm CPU and
then connect it through a 10µF electrolytic cap (+ at the rhythm
CPU side) to the amplifier's main CPU audio input.

Look at this crude PCB material...

The main voice preset sounds are made from each a static digital waveform
with simple volume envelope. The timbres have audible beeping components
due to the very low waveform sample resolution, but otherwise they resemble
more or less typical filtered multipulse squarewave. They all sound thin
and fairly harsh, which likely has also to do with the bad speaker and
amplifier. Due to there are no preset sounds listed, all sound names were
chosen by me. The "guitar" sounds a bit harsh and its decay phase ends
too soon. The "trumpet" plays much quieter than the other presets and has
a thin and harsh timbre that resembles bagpipes. The "pipe organ" is the
typical multipulse squarewave timbre that attempts to sound like a metal
pipe organ rank. The "e-piano" has a clarinet timbre, but starts to fade
silent after a second with held notes, and has a little sustain. During
decay the timbre turns a bit brighter (like a mild wahwah effect). The
"e-bass" has a bit hollow timbre that in the mid range reminds to a banjo
and also fades brighter during decay, but the envelope sounds too linear.
The "banjo" has a harsh timbre (like intended?) and a shorter decay envelope.
The "saxophone" is too harsh in the mid range and a delayed decay phase
prevents to play very short notes. The "mandolin" rings with about 8 Hz.
Unfortunately the keyboard matrix sometimes skips notes during very fast
play, and pressing more than 1 key plays a wrong note pitch (depending
on the key combination). A bit bizarre is also that when a key is held
down and a lower note is played, the instrument switches to the pitch of
the lower note and doesn't end the note before both keys are released.
Unlike the Golden Camel 7A, there is no vibrato effect (although
claimed on the box).

The percussion is made from grainy low- res samples those sound quite
distorted (with unmodified amp mine was extremely harsh and hissy); especially
the bongos clip noticeable. The scratch noise sounds like a zip. Both the
"snare" and "base" timbre resemble a timpani and could certainly sound
quite fat and bassy when the transistorized amp is modified a bit more.

The rhythm is produced by a digitally totally independent separate CPU,
and thus can be also started and stopped during demos etc. without interfering
with the main CPU in any way. Unfortunately my first rhythm CPU badly suffered
of chip cancer; it played semi- random "jungle" rhythms after about half
a minute (depending on its temperature) because its internal sequencer
freaked out. Thus I later transplanted the intact rhythm CPU from another
specimen of this keyboard (which apparently has a bad amplifier because
it plays too quiet and distorts badly). With rhythm off, the drumpads play
each a percussion sample. Although there are only 4 drumpads, 3 additional
percussion can be played by pressing multiple pads together (e.g..
cl. cymbal + open cymbal = low bongo, cl. cymbal + open cymbal + base =
high bongo, snare + base = scratch). Also the leftmost 7 keys are wired
parallel and thus do the same like the 4 drumpads. With the 5th (rightmost)
drumpad button rhythm can be switched on and off. When on, it plays a monophonic
preset rhythm pattern (there is only one) of fixed speed, and the drumpads
now play each a different fill-in (7 in total) instead of the 7 percussion
sounds. Each fill-in pattern plays 2 times before it switches back to the
normal rhythm pattern. There is no tempo control. When a drumpad sound
was played before switching rhythm on, the rhythm starts with its corresponding
fill-in before the normal rhythm patterns begins. But with my faulty rhythm
CPU the pattern made more and more mess and turned into semi- random jungle
grooves and drumrolls when the instrument warmed up, and also the fill-ins
turned into shorter and semi- random patterns. I first though it were no
bug but a feature based on a random number generator, but it turned out
that the patterns stay longer stable when I reduced its supply voltage
(normally 3.4V, I added a trimmer for this), but at too low voltage (2V
and lower) the rhythm distorted and also stopped in the middle of a pattern
when cold. (The rhythm CPU is only powered through a voltage divider of
a few 100 Ohms and thus anyway didn't turn feelable warm even after long
operation.) With rhythm off, my rhythm CPU also started to play quiet click/
pop noises every 2 seconds when drumpads are played with rhythm off. The
clicking stops after starting and stopping rhythm again.

The
hardware after my upgrade...

This
is the rewired amp; the electrolytic cap to the right reduces rhythm distortion.
The trimmer to the left reduces the supply voltage of my faulty rhythm
CPU (which I later removed).

Like the preset sounds, also the demos are switched in a sequence by pressing
any of the {"A".."L"} button (those are wired parallel) multiple times.
The demos are (unlike the manual keyboard play) 2 note polyphonic and employ
the currently selected preset sound for both voices. With the "guide" button
the instrument switches into an "any key play" mode, in which you can step
through the monophonic main voice of the demos by pressing keyboard keys
(the demos play only monophonic here).

The 22 demo musics are:

Twinkle Twinkle Little Star

?

Row, Row, Row Your Boat

Old MacDonald had a Farm

Little Brown Jug

?

Pop Goes the Weasel

Are You Sleeping?

?

Happy Birthday

Little Bee/ Hänschen Klein

? (Chinese tune?)

Mary had a Little Lamb

Twinkle Twinkle Little Star [different version]

Yankee Doodle

?

Puff, the Magic Dragon

10 Little Indians

This Old Man

London Bridge is Falling Down

Oh Susanna

?

Regarding the Yongmei naming conventions, the GC-11AB was
possibly also released as MS-11AB or YM-11AB. Possibly the
"AB" refers to the main CPU name, thus model names ending on "AB" may hint
to the same main CPU. The direct predecessor of this instrument was the
Golden
Camel 7A. A successor (with also 37 real and 7 fake drumpad keys
but more modern hardware) was the
Miles
3738. The name "Miles" may be an odd abbreviation of Meisheng,
the keyboard division of the infamous company Yongmei (see here
for their website). Another such keyboard (with similar cable mess inside)
is the MeiKe MK-320B,
which has 3 different spellings of its brand name on its case.